Gaia Theory

by talkbackty on Apr 7, 2012

Part 7 of the A to Z Blogging Challenge. To see all entries, click here.

Ever have one of those moments when you desperately wish you were smarter? It happened to me as I was trying to formulate some thoughts on the Gaia Theory. It's a strange thing to read sentences, understand specific words, but be unable to fully grasp the meaning. My mental chatter went like this, "Okay. Got it. Interesting...I have no idea what this guy is talking about."

While the Gaia Theory at first glance sounds like some hippie version of, "everything is one, man" the actual science is fascinating. Even if it is a little above my head. The original hypothesis was suggested by James Lovelock who said that "all organisms and their inorganic surroundings on Earth are closely integrated to form a single and self-regulating complex system, maintaining the conditions for life on the planet." Instead of a planet that has trillions of individual organisms living on it, the planet herself is one system, exactly like our own bodies.

Think of that basic model children are taught about streams flowing to rivers flowing to oceans where precipitation occurs and rain falls, beginning the process all over. The Gaia Theory states that our planet and ecosystem are in the same type of closed loop, with all inputs forwarding the goal of keeping the planet primed for life to flourish.

The theory was proposed originally to address the unexplainable balances our biosphere has pulled off for billions of years. For example, ocean salinity has remained at 3.4%, oxygenation of the atmosphere hovers around 21%, and the surface temperature has not drastically altered for millennia (remember we are talking cosmic scale, yes temperature fluctuates between hot and cold, but it's never 78 degrees and sunny one day and -310 degrees the next. Think big picture). Despite the fact that according to models at the time none of these things should remain constant. Rivers continually dump salt into the ocean, atmospheric gases continually expand, contract and mix above our heads, and the sun puts out 25-30% more energy today than when life originally began.

Back when the Gaia Theory was still the Gaia Hypothesis, James Lovelock came up with a brilliant simulation that could test the concept of a planetary regulatory system. Named Daisyworld, the simulation used a planet with only two types of daises- one species black and the other white. The sun upped its energy production over time (just as ours does), which should have increased the surface temperature of the planet. When the planet was cool (think early in development) black daises flourished because they absorbed more light and eventually warmed the surface temperature of the planet enough for white daises to bloom. White daises reflect light, thus cooling the planet and acting as a balance to the black daises. What the simulation showed was that despite the sun's gradual increase of solar energy the surface temperature never fluctuated beyond the "prime zone" for daises to bloom. If the sun was turned down, black daises grew to raise the temperature of the planet, when the sun was turned up, white daises replaced the black ones and the planet cooled. This, effectively, was the first step in proving the Gaia Hypothesis.

Daisyworld was controversial when first introduced. Many scientists stated that because of the simplicity and lack of realistic variables the experiment was invalid. With the rise of computers capable of handling massive amounts of data, Daisyworld was revisited to prove/disprove the naysayers. Other factors were added, from the incredibly simple things like gray daises, rabbits and foxes to the complex like numerous flora and fauna, weather patterns and random death rates. Each time the simulation added biodiversity the planet became more efficient. The naysayers actually did point out Daisyworld's biggest flaw- simplicity. When complexities were added the system got better at preforming the Gaia Hypothesis.

After thirty years of work and numerous experiments from various scientific fields all pointing in the same direction, the Gaia hypothesis officially became a theory. In 2001, a thousand scientists at the European Geophysical Union meeting signed the Declaration of Amsterdam, starting with the statement "The Earth System behaves as a single, self-regulating system with physical, chemical, biological, and human components."

Which is kind of cool. Even if I barely understand it.